1. Field of the Invention
The present invention relates to video playback and more specifically to detecting and identifying faults during video playback.
2. Introduction
The TR 101 290 guideline identifies major fault measurement parameters, such as CRC errors, that are critical to the health and performance of an MPEG transfer stream. However, the guideline provides no dynamic real time method or logic to isolate and find the underlying cause of the major fault measurements. Currently, video networks with conform to the TR 101 290 guideline (such as in AT&Ts U-Verse) observe these measurements but do not have an automatic process in place to do anything with them. One current approach to fault management is to manually troubleshoot the root cause of major faults with MPEG analyzers, but this approach is slow and inefficient. This approach involves human intervention which is expensive and error prone. Further, the number of major faults scales linearly with the number of MPEG transfer streams. In a production environment where thousands or hundreds of thousands of data streams are transmitted, such an approach quickly becomes unmanageable.
MPEG CRC errors identify corrupt data in an MPEG program specific information table such as the program map table (PMT) and program association table (PAT). If PAT is missing then a decoder can do nothing; no MPEG video stream is decodable. The result of this is macroblocks or a blackout. A macroblock is a 16×16 block of pixels in a video. When data is not decodable, the macroblock is either not updated or not displayed at all, leading to a block of pixels that is out of sync with the rest of the video. Viewers of the video notice such macroblocks or blackouts very easily because they interrupt the motion and picture of the video. Similarly, program data is not decodable without PMT, which leads to macroblocking or blackout or other decoding problems.
Accordingly, what is needed in the art is a way to automatically isolate and resolve faults in network data streams.